The C-value paradox refers to the discrepancy between an organisms complexity and the amount of DNA (C-Value). For instance, salamanders and lungfishes have the largest genomes of120pg, while the C-value of humans is only 3.5pg[1]

The huge size of some genomes mainly contains non-coding DNA. Although the C-value paradox is widely accepted among higher evolved animals and plants, still it holds a correlation between the genome size and the and organism complexity among the least evolved the most primitive creatures. Why during evolution a huge amount of non-coding DNA evolved and then disappeared again is explained by the rule of mass extinction.